The unwanted build-up of static electricity on an insulated support is well known. This phenomenon occurs on any element having an insulating support surface.
In photographic elements, including electrophotographic elements, radiation-sensitive layers are usually coated on an insulating support. It has been the practice to reduce the electrostatic charge build-up by coating the surface of the support on which no photosensitive layers are coated with an antistatic composition. The latter surface is referred to herein as the back surface of the support.
In U.S. Pat. No. 4,272,616 the back surface is coated with a homogeneous antistatic composition comprising a hydrophilic binder, such as gelatin, containing a nonionic polyethylene oxide surface-active agent and an alkali metal thiocyanate, iodide, perchlorate or periodate. Such antistatic compositions are effective in reducing the surface resistivity of such supports to about 10.sup.11 ohms/sq at 30% relative humidity (RH). However, according to the patent, even at resistivities of 10.sup.11 some static marks are discernable in developed photographic elements in which such antistatic coatings are used. The appearance of such static marks indicates that it is desirable to reduce the surface resistivity of such photographic supports even lower.